Since the first installation of carpeting and upholstery, there have been innumerable ways and theories as to the best approach for keeping the carpeting and other fabric material clean, including wet versus dry cleaning, deep versus shallow cleaning, and invariably an equal number of instruments or tools to effect the cleaning process. The most commonly used cleaning method today is the process of applying cleaning fluid as a spray under pressure to the surface to both dissolve the dirt and stains and to scrub the fibers and simultaneously apply a vacuum or negative pressure to extract the cleaning fluid and the soil captured thereby. Although this relatively high pressure method is the method most commonly used, it has some disadvantages. First, it must be remembered that the very nature of the soiled surface defines that the majority of the soil will be at or near the surface of the fibers and, therefore, a high pressure cleaning tends to drive some of the surface soil and cleaning fluid deeper, thereby requiring a very powerful vacuum system to extract those particles which have been driven beneath the outermost surface. Further, the use of cleaning fluid under pressure, applied through conventional jets, likewise drives the fluid itself deeper, and the fluid that is not immediately removed by the vacuum source takes a significantly longer amount of time to dry. Again, an inconvenience; but further, if the carpeting is used prior to the time it is completely dry, it is more likely to become soiled. Further, the sprayed fluid is atomized and comes into contact with the air, causing significant heat loss, diminishing the cleaning power of the fluid.
Numerous different approaches to spraying cleaning fluid under pressure and then removing it with a vacuum are illustrated in the prior art supplied herewith but will not be discussed in detail.
Another approach to the cleaning of carpeting and upholstery has been the use of a rotating device wherein the entire machine is transported over the carpeting while the cleaning head is rotated about a vertical axis. Typically, these machines include a plurality of arms, each of which includes one or more spray nozzles or a vacuum source providing a more intense scrubbing action since, in general, more scrubbing surfaces contact the carpet. These devices are primarily illustrated in the patents granted to Monson, and again, these devices are listed in the prior art known to the inventor but not discussed in detail herewith.
A third body of material wherein the cleaning fluid is either attempted to be deflected or otherwise controlled is illustrated hereinbelow.
U.S. Pat. No. 4,137,600, granted to Albishausen on Feb. 6, 1970, discloses a cleaning apparatus wherein the cleaning fluid is changed into a liquid curtain by a baffle within the cleaning head.
U.S. Pat. No. 4,335,486, granted to Kochte on Jan. 22, 1982, discloses a surface cleaning machine wherein the cleaning fluid is deposited upon the surface of the carpet pile from a wick like device which is wetted with the cleaning fluid.
U.S. Pat. No. 4,649,594, granted to Grave on Mar. 17, 1987, discloses a cleaning head wherein the cleaning solution is sprayed through a narrow passage and some is wicked along the surface of the passage.
U.S. Pat. No. 5,157,805, granted to Pinter on Oct. 27, 1992, discloses a method and apparatus for cleaning a carpet wherein the cleaning fluid is sprayed by nozzle against the back of a striker plate and then flows downwardly and through the carpet to a pickup vacuum.
U.S. Pat. No. 5,561,884, granted to Nijland et al on Oct. 8, 1996, discloses a suction attachment spray member wherein the fluid is sprayed against the distributor plate, which creates a planar diverging liquid jet substantially filling the vacuum chamber.